SAN FRANCISCO — Uber released information about more than 5 million California passengers to state regulators during the second half of 2015, according to a report Tuesday that raises new questions about the scope of data the government collects from on-demand companies.

The release of Uber’s first “transparency report” highlights the continuing conversation in Silicon Valley about how much tech companies should cooperate with law enforcement and government requests for data. Other companies, including Google and Facebook, also release reports on requests for data to aid criminal investigations, but little attention has been paid to similar requests made by regulators, who can demand data without a warrant or subpoena, and who can shut down a company that doesn’t comply.

“Historically there hasn’t been a ton of public awareness or oversight around these issues,” said Gautam Hans, San Francisco-based policy counsel at the Center for Democracy & Technology, a nonprofit that focuses on Internet privacy issues.

Uber disclosed that it received four requests for data from the California Public Utilities Commission, the state agency that regulates taxis and on-demand transportation companies. In fulfilling those requests, Uber provided data on about 5.4 million passengers and 300,000 drivers. In two cases, Uber said it was able to narrow the scope of the requests after negotiating with the CPUC.

In a blog post, Uber said it often tries to narrow the scope of regulators’ requests, but it’s usually rebuffed.

“Of course regulators will always need some amount of data to be effective, just like law enforcement,” Uber wrote. “But in many cases they send blanket requests without explaining why the information is needed, or how it will be used.”

Hans says he worries regulators are starting down a slippery slope in the data they are requesting from on-demand companies.

“There’s very little to stop them from saying, ‘Give us more data and we’re still not going to tell you why, otherwise we’re going to shut you down,’ ” he said.

Uber reported requests from airport authorities separately, disclosing that it released information about 1.6 million passengers and 156,000 drivers nationally. Those releases were the result of 34 requests from airports in cities including Oakland, San Francisco and San Jose.

Uber also received requests from law enforcement for information on 408 passenger accounts and 205 driver accounts throughout the country, according to the report. The company fully complied with 32 percent of requests, and partially complied with 53 percent. The remaining 15 percent either were withdrawn or yielded no data.

Uber says most law enforcement requests were to help catch criminals booking rides with stolen credit cards. The requests from the CPUC mostly asked for trip data, such as the pickup and drop-off locations and the time of the trip, according to the company.

Though trip data may not include names, it still could be used in conjunction with other data to identify drivers and passengers, said Andrew Crocker, a staff attorney with the Electronic Frontier Foundation in San Francisco.

“I think it’s always concerning when location data and other possibly identifying data is being shared by third parties about you,” he said.

“I guess I would say that it doesn’t surprise me that data is being released,” Campbell said. “But I’m still not super happy about it.”

Uber joins more than 60 tech companies that have issued transparency reports since 2010, according to Access Now’s Transparency Reporting Index. The move comes less than a month after the FBI abandoned its controversial bid to force Apple to give it backdoor access to an iPhone linked to a terrorist attack in San Bernardino.

Uber says it has received no requests for information related to matters of national security.

For Brian Dougherty, a 66-year-old Uber driver from San Jose, the data release isn’t much of a concern.

“The government needs to know as much as they can know to protect us,” he said. “As long as we’re good citizens and we pay our taxes and all that good stuff, why should we be afraid?”

Data requests made by regulators: 33California passengers affected by data released to regulators: 5.419 millionCalifornia drivers affected by data released to regulators: 299,000Data requests made by airports: 34State and federal law enforcement requests: 415— All data is for July through December 2015.

Marisa Kendall covers housing for the Bay Area News Group, focusing on the impact local companies have on housing availability in the region. She's also written about technology startups and venture capital for BANG, and covered courts for The Recorder in San Francisco. She started her career as a crime reporter for The News-Press in Southwest Florida.

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